Portable refrigerator



FIG. 1 is a front elevational view of a portable refrigerator showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a perspective view thereof;

FIG. 8 is another perspective view thereof;

FIG. 9 is a front elevational view of the portable refrigerator in use;

FIG. 10 is a perspective view of the portable refrigerator in use; and,

FIG. 11 is a portion of the perspective view of FIG. 2 enlarged for magnification purposes.

The broken lines illustrate portions of the environment structure which forms no part of the claimed design. 

CLAIM The ornamental design for a portable refrigerator, as shown and described. 